autodesk forge – Deleting a BIM360/ACC File?

I’m trying something that seems straightforward – to delete an item within a BIM360/ACC project (which I know is actually to Post a new version that is deleted).

I’ve followed closely the instructions here:
aps.autodesk.com/en/docs/data/v2/tutorials/delete-and-restore-file/

My REST call is almost identical.

However, I’m receiving this error:
{“jsonapi”:{“version”:”1.0″},”errors”:[{“id”:”c235208c-c820-427c-beb1-f3c2858efb7b”,”status”:”400″,”code”:”BAD_INPUT”,”title”:”One or more input values in the request were bad”,”detail”:”Schema “versions:autodesk.core:Deleted -1.0″ was not found.”}]}

Any guidance that someone could offer?